Communication systems have been under extensive development in recent years. Several new services have been developed. Different data and multimedia services are attractive to users, and communication systems should provide a sufficient quality of service.
The popularity of Internet-based services has increased. One of such services is Internet-based voice calls (Voice-over-IP) where a speech or video phone call is realized with an Internet Protocol (IP) connection between personal computers.
The developed wireless communicating systems are utilizing IP-based connections and provide browsing and other IP-based services to customers. The users expect to have similar service using wireless user equipment as personal computers.